CVE-2026-47254

MEDIUM
Published Jul 21, 2026 CWE-125

Description

libheif is a HEIF and AVIF file format decoder and encoder. Prior to version 1.22.0, `Track::init_sample_timing_table()` in `libheif/sequences/track.cc` stores an out-of-bounds chunk index (`m_chunks.size()`) into `m_presentation_timeline` when the number of chunks defined in the `stco` box is less than the number of samples in `stsz`. A subsequent call to `heif_track_get_next_raw_sequence_sample()` reads `m_chunks[chunk_idx]` with that OOB index, causing a heap-buffer-overflow. Version 1.22.0 fixes the issue.

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CVSS v3.1 Score

6.1
MEDIUM
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H

Weakness Type (CWE)

CWE-125 Out-of-bounds Read

References

Frequently Asked Questions

What is CVE-2026-47254? +
libheif is a HEIF and AVIF file format decoder and encoder. Prior to version 1.22.0, `Track::init_sample_timing_table()` in `libheif/sequences/track.cc` stores an out-of-bounds chunk index (`m_chunks.size()`) into `m_presentation_timeline` when the number of chunks defined in the `stco` box is less than the number of samples in `stsz`. A subsequent call to `heif_track_get_next_raw_sequence_sample()` reads `m_chunks[chunk_idx]` with that OOB index, causing a heap-buffer-overflow. Version 1.22.0 fixes the issue. It has a CVSS v3.1 base score of 6.1 (MEDIUM).
How severe is CVE-2026-47254? +
CVE-2026-47254 has a CVSS v3.1 score of 6.1 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.
How do I check if I'm vulnerable to CVE-2026-47254? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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